[One case of 2q37 deletion syndrome: clinical and genetic diagnosis].

OBJECTIVE: To diagnose a new born baby with 2q37 deletion syndrome by comprehensive use of cytogenetic and molecular techniques and to investigate the phenotype characteristics and applicability of array-comparative genomic hybridization (array-CGH) and multiplex ligation-dependent probe amplification (MLPA) for detection of this syndrome. METHOD: Following conventional chromosome preparation, G banded karyotyping was performed.Genomic DNA was extracted using standard procedures, which were then analyzed by array-CGH and MLPA. RESULT: The patient presented with a typical face, special fist posture and congenital heart disease in 2q37 deletion syndrome. A 4.709 Mb deletion at 2q37.3 (chr2:237, 967, 852-242, 677, 269.NCBI36/hg18, including genes from COL6A3 toPDCD1) was detected by array-CGH. The results of MLPA and G banded karyotyping confirmed the existence of this deletion. CONCLUSION: 2q37.3 deletion was determined to be the cryptic cause of this case.2q37 deletion syndrome has some clinically recognizable characteristics. And array-CGH is a powerful technique for the accurate diagnosis and genotype-phenotype correlation study of this syndrome.

[Analysis of fetal chromosomal karyotype and etiology in 252 cases of early spontaneous abortion].

OBJECTIVE: To investigate the relationship between fetal chromosomal karyotype and early spontaneous abortion, and the effect of the environmental factors on spontaneous abortion. METHODS: Choronic villi from 252 cases of missed abortion were sampled as patient group and 50 normal pregnancies as control group. Chorionic villi were cultured and karyotype analysis was performed by G-banding. Clinical information was collected. RESULTS: The rate of chorion chromosome abnormality in the patient group was 58.09%, significantly higher than that in the control group (4.17%) (P<0.01). Among the 140 cases of karyotype abnormalities, 81 were trisomy, 29 were monosomy X and 17 were polyploidy, accounting for 57.86%, 20.71% and 12.14% of total abnormalities, respectively. Long time and low dose radiation exposure of the pregnant female seemed to be related with spontaneous abortion(P<0.01). CONCLUSION: Chorion chromosome abnormality is a major reason of early spontaneous abortion and karyotype analysis of chorionic villus is of clinical importance. For pregnant women, long-term exposure to computers and television seems a risk factor for missed abortion.